In the field of the optical communications, for example, a laser diode module is used in which a laser diode (LD) chip for outputting light is coupled to an optical fiber for emitting light from the laser diode chip to form a module. In fabricating this type of the laser diode module, a method for accurately and easily aligning the laser diode chip with the optical fiber is desired.
The present invention is to provide an alignment method of a laser diode chip with an optical fiber, an alignment apparatus adapted to the alignment method and a laser diode module aligned by employing the alignment method.
An alignment method of a laser diode chip with an optical fiber of the invention comprising the steps of:
facing the laser diode chip with a coupling end face of the optical fiber;
aligning a position in the Z direction where the optical fiber is aligned with the laser diode chip at a position in the Z-axis direction of an optical axis of the laser light; and
aligning a position in the XY direction where the optical fiber is aligned with the laser diode chip at a position in the X direction and the Y direction on the XY plane of an X-axis and a Y-axis orthogonal to the Z-axis,
wherein the step of aligning a position in the Z direction has the following steps of:
acquiring light power data at a Z position where the coupling end face of the optical fiber is moved relatively with respect to the laser diode chip in the Z-axis direction to measure a light power received by the optical fiber and light power data is acquired at every predetermined reference movement, in a state that the laser diode chip is faced to the coupling end face of the optical fiber; and
setting an alignment position in the Z-axis direction where the alignment position for the optical fiber in the Z-axis direction is determined with respect to the laser diode chip based on the light power data at every predetermined reference movement.